1. Field of the Invention
This invention relates to a method for repairing the exterior of a building or other concrete structures to prevent flaking of exterior materials, such as bricks and tiles, which is brought about by cracking of the concrete wall base of the structure or by other possible causes.
2. Description of the Prior Art
The concrete wall base or groundwork of a building, concrete structure and so on are generally covered with exterior material such as tiles and bricks. Such exterior material is fixed onto the surface of the concrete wall base by using cement material such as mortar. The concrete wall base with the cement material is apt to crack owing to the influences of the weather and vibrations such as earthquakes. As a result, the strength of the union between the exterior materials and the wall base would decrease gradually by infiltration of rain water into the wall base through the cracks in the wall or by other possible causes. Thus, the exterior materials may flake off from the wall base and injure a passer-by, thereby possibly leading to a social problem.
In order to prevent such accidents, there have been performed visual inspections, sound inspection by which abnormalities in the wall base are found by tapping against the wall surface of the structure with a hammer and listening for changes in sound, and other non-destructive inspections. When a defective portion such as a crack in the concrete wall base or mortar setting bed covered with the tiles, the defective portion is repaired by boring holes in mortar joint portions between the adjacent tiles by use of a vibration-type drilling device, and driving anchor bolts into the holes.
Such a method of boring the holes in the mortar joint portions between the tiles and inserting the anchor bolts into the holes, might strengthen the wall base and mortar cement setting bed, but it has little effect on the exterior tiles. Furthermore, since the mortar setting bed is weak in strength, how the tiles are fixed relative to the concrete wall base is a problem. Therefore, flaking of the tiles remains a hazard.